1. Field of the Invention
The present invention relates to an image forming apparatus, a method of setting a fixing temperature, and a computer program product.
2. Description of the Related Art
Most of the recent image forming apparatuses such as copiers have power-saving functions. For example, some copiers maintain a fixing unit at a fixing temperature by applying heat with a heater and fixing toner to a paper sheet. These copiers save electricity by stopping or reducing power supply to the heater during standby without copying to maintain the temperature of the fixing unit at less than the fixing temperature.
Thus maintaining the fixing unit at a low temperature during standby allows power saving. A user, however, needs to wait until the completion of a preparation operation for increasing the temperature of the fixing unit to the fixing temperature even when the user wants to copy urgently, which is inconvenience.
On this account, Japanese Laid-open Patent Publication No. 06-189048 discloses a technique of a copier that detects a person's approach in a power saving mode, determines whether the person is the user of the copier, and then releases the power saving mode when the person is determined as the user. This technique allows the preparation operation to be started before a user reaches the installation site of the copier and reduces the waiting time.
In the technique disclosed in Japanese Laid-open Patent Publication No. 06-189048, power saving is released whenever a user approaches. Because of this, disadvantageous situations occur such that the power saving mode is released even when a user intending to use another device near the copier approaches the copier, leading to unnecessary power supply.
Japanese Laid-open Patent Publication No. 2007-049308 discloses an image forming apparatus dealing with the disadvantages. This image forming apparatus acquires a user identification information (ID) when a user holding an employee ID card to which an integrated circuit (IC) tag storing the user ID is attached approaches, and refers to the past usage history. The image forming apparatus then forecasts the use of an application for an output operation (image forming process) (called an output application, hereinafter) and starts a preparation operation including warming up of the fixing unit. Both Power saving and user convenience can be thus achieved.
In the image forming apparatus disclosed in Japanese Laid-open Patent Publication No. 2007-049308, the fixing temperature of the output application is not optimized (but is fixed) depending on the output setting (the number of sheets, a paper type, a paper thickness, a color mode, etc.). As a result, for example, the small number of output sheets per one action results in unnecessary power consumption due to excessive power supply.
The fixing temperature when the number of output sheets per one action is smaller (6 sheets or smaller, for example) can be set lower to reduce power consumption than when the number of output sheets (50 sheets, for example) is larger. However, the fixing temperature is typically set high in case the number of output sheets per one action is large. In general, in image forming apparatuses placed in offices, the number of output sheets per one action is often small under present circumstances, leading to increase in unnecessary power consumption due to excessive power supply.
In view of the above, there is a need to provides an image forming apparatus, a method of setting a fixing temperature, and a computer program product that enable reduction in unnecessary power consumption due to the setting of high fixing temperature.